Imagine each track in a group had its own channel.
And you could add multi-in DSP effects to a group.
WIth the effect one could then combine the signals of the individual channels with operators (multiply, add, divide ...)
or in other more complex ways.
This would open up incredible possibilities.

In a way you could influence how a group mixes its tracks.

If the group`s mixer would have selectable operators - it sure would be a lot of fun.

It would also be great if the native DSP API would be accessible to users.
But that´s another story - For now, being able to use multi-in VSTs on groups (the way decribed above) would also be great.